On 2010-08-30 11:57 +0200, Pekka Enberg wrote:

On Mon, Aug 30, 2010 at 12:36 PM, Sven Joachim svenjoac@gmx.de wrote:

...

On my laptop which has a 1280x800 display, only the upper left 848x480 pixels are used on the console in 2.6.36-rc3.  The resolution is correct, but /sys/class/graphics/fb0/modes looks like this:

U:848x480p-0

This is a regression from 2.6.35.  The graphics card according to lspci:

00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03)

Yeah, you're not alone on this:

http://lkml.org/lkml/2010/8/23/452

Incidentally, I did not notice the problem initially described in this thread, and 2.6.36-rc2 actually seems OK for me. But after this commit:

commit 9559fcdbff4f93d29af04478bbc48294519424f5 Author: Jesse Barnes jbarnes@virtuousgeek.org Date: Tue Aug 24 11:31:16 2010 -0700

drm/i915: fix vblank wait test condition

When converting this to the new wait_for macro I inverted the wait condition, which causes all sorts of problems. So correct it to fix several failures caused by the bad wait (flickering, bad output detection, tearing, etc.).

Reviewed-by: Chris Wilson chris@chris-wilson.co.uk Tested-by: Sitsofe Wheeler sitsofe@yahoo.com Signed-off-by: Jesse Barnes jbarnes@virtuousgeek.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org

@ -992,7 +992,7 @@ void intel_wait_for_vblank(struct drm_device *dev, int pipe)

/* Wait for vblank interrupt bit to set */ if (wait_for((I915_READ(pipestat_reg) & - PIPE_VBLANK_INTERRUPT_STATUS) == 0, + PIPE_VBLANK_INTERRUPT_STATUS), 50, 0)) DRM_DEBUG_KMS("vblank wait timed out\n"); }

only the upper left 848x480 pixels of the display are used for the framebuffer. Booting with the video=1280x800 commandline option works around this problem.

Sven